When McCrea presented his master's thesis, he jokingly
You know, two dinosaurs mating.
Reptilian passion captured in stone.
The professors were not visibly amused.
(Continuedfrom page 8) ruled by titanic crea
tures, thriving all over the globe from 230 to 65
million years ago, during the Mesozoic era.
And the field has charms that the laboratory
can't match. The field is the staging ground
for that whole Indiana Jones thing, for the
type of charismatic, rock-star scientists who
hang out in dinosaur graveyards with shovels,
picks, plaster, graduate students, and personal
documentary film crews.
But perhaps the very glamour of dinosaurs
has spawned the backlash, the willful retreat to
scientific basics by Greg Erickson and research
ers like him. Most scientific disciplines aren't
caught in the gravity well of public fascination.
If you study fossil mollusks, for example, you
aren't likely to be asked to become a scientific
adviser for a Hollywood blockbuster. No one has
snail fever. But dinosaur fans are insatiable for
information. The new generation of scientists
wants to put constraints on all the hypotheses
flying around, and they think that the truth
about dinosaurs-and dinosaur behavior
won't be uncovered with bones alone.
"For 20 years we've done what we call arm
waving," says Jack Horner, a legendary bone
collector. "We've made hypotheses based on
very little evidence. Now we're sitting down,
we're saying, 'We've got all these ideas, are
they real?'"
Horner can arm-wave like a champ, as he
will admit. Since 1991 he's been arguing, for
14 NATIONAL GEOGRAPHIC * MARCH 2003
example, that Tyrannosaurus rex, the very
emblem of predation, the killer of killers, was
actually just a scavenger, an eater of the dead.
An overgrown turkey vulture! Those banana
size teeth weren't for ripping live flesh, says
Horner, they were for crushing the bones of a
carcass. This is vintage contrarianism, and
Horner so far has failed to persuade many of
his peers, who point out
that T7rex need not have been
one thing or another. Hyenas, for example, are
scavengers one day, predators the next.
But in any case this is precisely the kind of
argument that can't be won by speaking louder
than one's opponents. Science requires data.
Science requires that ideas be subjected to
tests. And paleontology-if the new generation
has its way-will be seen as a no-nonsense
field, a hard science, in addition to being a thrill
ing subject built around the bones of large,
scary animals.
Shis is where we have the rhino heads
Sand the manatee heads," Lawrence Wit
mer is saying. "We've got a whole bin of ostrich
heads and necks. We've got ducks and geese.
Here's a bag of alligator parts."
We're in the deep freeze of his laboratory at
Ohio University in Athens. Witmer has quite the
collection of heads. They belonged to creatures
that died, or were killed for some other reason,
and were then obtained by Witmer for research.